Catheter system for introducing an expandable stent into the body of a patient

Abstract

This disclosure relates to a catheter system for introducing a heart valve stent into the body of a patient. The catheter system includes a catheter tip having a seat portion for accommodating the stent in its collapsed state and a stent holder for releasably fixing the stent, wherein the seat portion is constituted by a first sleeve and a second sleeve, said sleeves being moveable relative to each other and relative to the stent holder, and a catheter shaft for connecting the catheter tip to a handle.

What is claimed is: 
     
       1. A delivery system for introducing an expandable stent having a distal end and a proximal end into a heart of a patient, the delivery system comprising a distal end portion comprising:
 a catheter tube; 
 an end support coupled to a distal end of the catheter tube, a proximal surface of the end support being tapered; 
 a stent holder comprising an outer surface that is tapered, the stent holder positioned at the distal end portion and configured to directly mate with a proximal end of the expandable stent such that a distal end of the expandable stent is disposed closer to the end support than the proximal end of the expandable stent; and 
 a sheath movable relative to each of the catheter tube and the stent holder; 
 a handle at a proximal end of the delivery system, the handle configured to manipulate at least the stent holder, 
 wherein the distal end portion of the delivery system is configured to house the expandable stent comprising at least two positioning arches in a collapsed configuration such that the expandable stent is releasably engaged with the stent holder at the proximal end of the expandable stent, 
 wherein the handle comprises at least one actuator for sequentially releasing the expandable stent from the distal end portion, and 
 wherein the at least one actuator is configured to permit the at least two positioning arches to expand while at least a portion of the expandable stent remains in the collapsed configuration. 
 
     
     
       2. The delivery system of  claim 1 , wherein the distal end portion further comprises an end tip that is cone-shaped. 
     
     
       3. The delivery system of  claim 1 , wherein the catheter tube defines a lumen configured to receive a guidewire. 
     
     
       4. The delivery system of  claim 1 , further comprising a shaft positioned between the handle and the distal end portion, wherein the shaft is flexible thereby permitting the distal end portion to navigate the aortic arch. 
     
     
       5. The delivery system of  claim 1 , wherein the handle is configured to rotate the distal end portion about a longitudinal axis of the distal end portion. 
     
     
       6. The delivery system of  claim 1 , wherein the stent holder is configured to releasably engage retaining elements extending from a proximal end of the expandable stent. 
     
     
       7. The delivery system of  claim 1 , wherein the distal end portion comprises at least one radiopaque marker for positioning the distal end portion in the aortic valve. 
     
     
       8. A method for introducing an expandable stent having a distal end and a proximal end into a heart of a patient, the method comprising:
 advancing a distal end portion of a delivery system through an aortic arch of a patient towards an aortic valve of the patient, the distal end portion comprising:
 a catheter tube; 
 an end support coupled to a distal end of the catheter tube and comprising a proximal surface that is tapered; 
 a stent holder comprising an outer surface that is tapered, the stent holder positioned at the distal end portion and configured to directly mate with a proximal end of the expandable stent such that a distal end of the expandable stent is disposed closer to the end support than the proximal end of the expandable stent; and 
 a sheath movable relative to each of the catheter tube and the stent holder; 
 a handle at a proximal end of the delivery system, the handle configured to manipulate at least the stent holder and comprising at least one actuator for sequentially releasing the expandable stent from the distal end portion; 
 
 introducing the distal end portion through the aortic valve, wherein the expandable stent comprises at least two positioning arches and is housed in the distal end portion in a collapsed configuration such that the expandable stent is releasably engaged with the stent holder at the proximal end of the expandable stent; 
 manipulating the at least one actuator of the handle to permit the at least two positioning arches to expand while at least a portion of the expandable stent remains in the collapsed configuration; and 
 releasing the expandable stent from the stent holder to cause the expandable stent to transition to an expanded configuration within the aortic valve. 
 
     
     
       9. The method of  claim 8 , wherein releasing the expandable stent comprises manipulating the stent holder using the handle to release the expandable stent. 
     
     
       10. The method of  claim 8 , wherein the delivery system further comprising a flexible shaft positioned between the handle and the distal end portion, and further comprising using the handle to cause the flexible shaft to bend to navigate the aortic arch. 
     
     
       11. The method of  claim 8 , further comprising sequentially releasing the expandable stent from the distal end portion using the handle. 
     
     
       12. The method of  claim 8 , further comprising rotating the distal end portion about a longitudinal axis of the distal end portion using the handle. 
     
     
       13. The method of  claim 12 , further comprising aligning the expandable stent with the aortic valve. 
     
     
       14. The method of  claim 8 , wherein releasing the expandable stent from the stent holder comprises releasing retaining elements extending from a proximal end of the expandable stent. 
     
     
       15. The method of  claim 8 , wherein the distal end portion further comprises at least one radiopaque marker, and further comprising visualizing the distal end portion in the aortic valve using the at least one radiopaque marker.